Quaternary ammonium compounds in pretreatment of hair before shampooing with an anionic shampoo

ABSTRACT

This invention is concerned with the pretreatment of hair on the human head, preceding shampooing the hair with anionic type hair shampoos, and with compositions for effecting such pretreatment, to obtain highly improved manageability of the hair after shampooing and with improved fullness, combability and other desired properties of the hair. The pretreatment compositions utilize readily water-soluble quaternary ammonium compounds, particularly in combination with certain agents, notably polyethylenimines and N-ethanolacetamide, and desirably together with various supplemental ingredients.

This invention relates to improvements in the treatment of hair on thehuman head. As used hereafter, the term "hair" is to be understood tomean hair on the human head.

In connection with the treatment of hair, it has been a common practice,after washing or shampooing the hair, to subject it to various hairtreatment compositions to impart certain desirable properties thereto.Among such hair treatment compositions, used after the washing orshampooing of the hair, are those commonly called, or characterized as,rinses and conditioners, which are formulated or designed to impartsoftness or smoothness of feel, luster, body or weight, manageability,combability and other properties to the hair. This is, in general,achieved by effecting a deposit on the hair of a film of a charactersuch as serves, to some extent or other, to impart to the hair one ormore of the above-stated properties or characteristics. The aforesaidhair treatment compositions may take various forms, such as aqueous oraqueous-alcoholic solutions, lotions, or dispersions; creams, etc.

Among such hair treatment compositions which have heretofore been knownand some of which have been used to a substantial commercial extent arethose of the type which contain cationic agents, generally of thequaternary ammonium type and exemplified by compounds such ascetyldimethylbenzyl ammonium chloride; cetyldimethylethyl ammoniumchloride; stearyldimethylbenzyl ammonium chloride; distearyldimethylammonium chloride; laurylisoquinolinium bromide; and quaternary ammoniumsalts of homopolymers of dimethyl-or diethyl-aminoethyl methacrylate.Such hair treatment compositions are commonly compounded in the form ofemulsions or dispersions and, as indicated above, they are applied tothe hair after first washing the hair with a soap or a hair shampoowhich commonly contains, as an ingredient thereof, soaps or anionicsynthetic detergents, followed by thorough rinsing of the hair withwater, after which the aforesaid hair treatment compositions are appliedto the hair. The thorough rinsing of the hair with water is effected toremove as much of the soaps or anionic detergents as possible since,otherwise, precipitates form in the hair by virtue of theincompatibility of the cationics with the anionics.

Cationic agents are known generally to be substantive to the hair and,therefore, in the use of the above-mentioned hair treatment compositionswhich contain cationic agents, a film or deposit is formed on the hairshafts, by adsorption, and due to reaction between the cationic agentand the keratinous material of the hair. The character and the amount ofsuch film as is formed and deposited on the hair influence theproperties and characteristics of the hair.

The foregoing known practices serve a distinctly useful purpose and, ingeneral, are reasonably effective in imparting to the hair, to at leasta fairly good extent, properties and characteristics of the naturedescribed above. They are frequently, however, less effective than isdesired, particularly with respect to the matter of control of theweight of the hair and its manageability.

The present invention is based upon discoveries which have been madewhich enable more effective management of the hair with excellent andimproved results in one or more respects with regard to body or weightcontrol, combability, fluffiness and spring and, in general, desiredconfiguration control of the hair.

In accordance with the present invention, the hair is first treated withan aqueous composition which contains certain types of quaternaryammonium compounds and thereafter, without intermediate rinsing, iswashed with soap or, more desirably, with a formulated shampoo of thetype which contains an anionic cleanser or detergent such as soapsand/or anionic synthetic detergents, all as is described in detailbelow. It may, however, here be observed, and as will be noted furtherbelow, that no novelty is claimed broadly in the practice of treatinghair first with an agent which has cationic properties and then followedby washing the hair with a shampoo containing an anionic detergent.

Pursuant to the present invention, the hair pretreatment composition,which is applied to the hair prior to the washing step with soap orshampoo containing soap and/or an anionic synthetic detergent, comprisesan aqueous composition which contains a readily water-soluble quaternaryammonium compound whose solubility is such that, in water at roomtemperature, it forms a solution, in use concentrations of at least0.5%, by weight of the solution, which is clear to the naked eye. Sincethe use concentration of the quaternary ammonium compound may be as highas about 4%, by weight of the solution, those quaternary ammoniumcompounds which are utilized in such concentrations should have watersolubilities such that, when looked at with the naked eye, they appearto be clear, even though, in actual fact, micelles or agglomerates maybe present which would establish that the apparently clear solution isnot a true solution. For the purposes of the present invention,reference to a clear solution means a solution which is optically clearto the naked eye unaided by sophisticated optical instruments.

While, as stated above, the quaternary ammonium compounds which are usedin the hair pretreatment compositions of the present invention shouldhave the solubility characteristics to form clear solutions in water atroom temperature at the use concentrations, in the range of 0.5 about4%, and while the finished hair pretreatment compositions ascommercially marketed are most desirably in the form of clear aqueoussolutions, the hair pretreatment compositions can be made up in otherforms, for instance, as cream products, with the use of acid-stabilizedglyceryl monostearate or other agents. However, since the hair, afterthe application thereto of the pretreatment composition, and withoutintermediate rinsing, is to be washed with soap or with a shampoocontaining soaps and/or anionic synthetic detergents, ingredients shouldnot be included in the pretreatment composition which would undulyinterfere with or cause undue difficulties in the washing step with thesoap or said hair shampoos.

In addition to possessing the water solubility discussed above, thequaternary ammonium compounds should also contain one long chain alkylradical attached to the central nitrogen atom of the quaternary ammoniumcompound. The long chain alkyl radical should be selected so that itdoes not result in loss of the stated water-solubility propertiesdesired in the quaternary ammonium compound. Hence, while, in general,the long chain alkyl radical may contain from 8 to 18 carbon atoms, itis particularly desirable that it contain from 10 to 14 carbon atoms,and, better still, predominately 12 carbon atom in most cases. Theabsence of a long chain radical, or the substantial equivalent thereofas noted below, will result in an inadequately satisfactory coating onthe hair shaft and an unsatisfactory coating or deposit in the pores orcrevices or on the hair shaft after the shampooing step, as hereafterpointed out.

At least most of the quaternary ammonium compounds, which are useful inthe production of the hair pretreatment compositions of and used inpracticing the present invention, can be represented by the formula##STR1## where R¹ is a C₈ -C₁₈, particularly C₁₀ -C₁₄ with C₁₂predominating, alkyl radical; each of R², R³ and R⁴ is a C₁ -C₃ alkylradical, particularly a methyl radical; and the total of the number ofcarbon atoms in R², R³ and R⁴ generally, and most desirably, should notexceed 6; and A is an innocuous inorganic or organic anion, particularlyhalogen such as chlorine or bromine, but which may also be other anionssuch as sulfate, sulfite, phosphate, nitrate, nitrite, acetate,methylsulfate, and toluenesulfonate.

Illustrative examples of such quaternary ammonium compounds areoctyltrimethyl ammonium chloride; decyltrimethyl ammonium chloride;lauryldimethylethyl ammonium chloride; dodecyltrimethyl ammoniumchloride; tetradecyltrimethyl ammonium chloride; hexadecyltrimethylammonium chloride; octadecyltrimethyl ammonium chloride; mixed higheralkyl trimethyl ammonium chlorides containing mixtures of predominatelyC₈ -C₁₈ alkyl radicals such as are derived from sources such as coconutoil or special fractions thereof high in C₁₂, soya bean oil, cottonseedoil, babassu oil, palm oil, etc.; and corresponding compounds whereinthe anion is other than halogen, as noted above.

To obtain the desired good solubility in water of the quaternaryammonium compounds, there should be only one C₈ -C₁₈ alkyl group in thecompounds. However, quaternary ammonium compounds with suitablesolubility can be used such as dihexyldimethyl ammonium chloride orbromide, or similar compounds with anions other than chlorine orbromine. Quaternary ammonium compounds in which all of the alkyl groupsare of low molecular weight, such as tetramethyl -- or tetraethylammonium chloride or bromide are unsatisfactory because, while they arevery soluble in water, they do not form a satisfactory film on the hairand do not adequately "weight" the hair, and, in any event, they do notimpart the desired properties to the hair such as are achieved throughthe use of compounds such as, for instance, dodecyltrimethyl ammoniumchloride or bromide when used in accordance with the practice of thepresent invention.

Various other quaternary ammonium compounds, which do not fall withinthe scope of the foregoing formula, which formula encompasses theparticularly desirable compounds for use in the practice of the presentinvention, can, nevertheless, be used with reasonably good results,illustrative examples of which are long chain or C₈ -C₁₈alkyldimethylbenzyl ammonium chlorides such as dodecyldimethylbenzylammonium chloride; tetradecyldimethylbenzyl ammonium chloride;cetyldimethylbenzyl ammonium chloride; dodecylpyridinium chloride;cetylpyridinium chloride; n-dodecyldimethyl-p-chlorobenzyl ammoniumchloride; N-(lauroylcolaminoformylmethyl)-pyridinium chloride;diisobutyl-phenoxyethyldimethylbenzyl ammonium chloride;9-octadecenyldimethylethyl ammonium chloride; myristyl-r-picoliniumchloride; diisobutylcresoxyethyldimethylbenzyl ammonium chloride; andamine oxides such as dodecyldimethylamine oxide; dodecyldiethylamineoxide; and 9-octadecenyldimethylamine oxide; which amine oxides, undercertain known acid conditions, are converted into or function asquaternary ammonium compounds.

It will be understood that any two or more of the foregoing, or other,quaternary ammonium compounds can be used so long as they meet thecriteria set forth above and are not mutually incompatible.

In place of the foregoing quaternary ammonium compounds, thecorresponding sulfonium and the corresponding phosphonium compounds canbe used with at least fair results but, for a variety of practicalreasons, they are of distinctly secondary significance.

It is especially advantageous, in the more important embodiments of thepresent invention, to utilize, in conjunction with the quaternaryammonium compounds in the hair pretreatment compositions, minorproportions of (a) N-ethanolacetamide or lauric ethanolamide or coconutoil mixed fatty acid ethanolamides, and (b) polyethylenimines.

The aforesaid (a) ingredient has heretofore been used in hair treatmentcompositions and no novelty is claimed broadly in its use in thetreatment of hair. It serves to aid in the retention by the hair of acertain amount of water and plays a role in the control of hair weightor the weight of the filmed hair.

The polyethylenimines, which are made by polymerizing ethylenimine, maybe used in the form of ethylenimine polymers, or polyethylenimines, ofvariable molecular weights, advantageously of the order of M.W. about10,000 to about 70,000, with a good average in the range of about 40,000to about 60,000. In conjunction with the quaternary ammonium compoundsthey cooperate and function to form a coating or film on the hair shaftsof a character such that exceptional manageability or control and lusterand natural appearance are imparted to the hair after the step ofwashing the hair with the soap or anionic shampoo is effected followedby rinsing out the soap or shampoo with water.

It may also be noted that no novelty is claimed in the use, broadly orper se, of polyethylenimines of varying molecular weights, includingmolecular weights of the order of 60,000, for the treatment of hair.Thus, they have been used in hair shampoos to obtain increased sheen,body and manageability of the hair and improved combability. They havealso been used in treating hair prior to washing or shampooing the hairwith anionic shampoos. It is known that the polyethylenimines arethemselves cationic in character under certain conditions and aresubstantive to hair. However, it has been found that the objectivesbehind their use, in hair shampoos or for treating hair prior toshampooing with soap or anionic shampoos, are inadequately achieved.Tests carried out with the washing or shampooing of hair with anionicdetergent shampoos containing added polyethylenimines, as well as testscarried out by pretreatment of hair using polyethylenimines alonefollowed by washing with soap or with anionic shampoos, have givenresults which have left much to be desired. Used in conjunction with thequaternary ammonium compounds in a pretreatment of the hair, followed bywashing or shampooing with soap or anionic detergent shampoos, accordingto the present invention, the results obtained have been markedlysuperior.

The particularly important aspects of the present invention, therefore,involve the utilization, for the pretreatment of the hair, of aqueouscompositions, and especially clear solutions, containing water-solublequaternary ammonium compounds in conjunction with polyethylenimines, andmost desirably also in conjunction with N-ethanolacetamide or theaforesaid ethanolamides, and the proportions involved will generallyfall within the following approximate ranges in terms of % by weight ofthe pretreatment compositions:

    ______________________________________                                                             %                                                        ______________________________________                                        Quatenary ammonium compound                                                                          0.5 to 4                                               Polyethylenimine       0.2 to 5                                               N-Ethanolacetamide or ethanolamide                                                                   3 to 18                                                Water                  70 to 90                                               ______________________________________                                    

A preferred range of proportions is 1.5 to 2.5%, generally about 2%, ofthe quaternary ammonium compound; 0.4 to 2%, generally about 0.5 to1.5%, of the polyethylenimine; 3 to 18%, generally about 4 to 15%, ofthe N-ethanolacetamide or ethanolamide; and the balance verypredominately water, generally from about 70 to about 85%, preferablyabout 75%.

Supplemental agents may and, generally, are desirably included in thehair pretreatment compositions such as, for instance, one or more ofthickeners or viscosity modifiers, proteins, silicone hair lubricants,preservatives, perfumes, solubilizers for said perfumes, coloringagents, etc.

In those instances in which polyethlenimines are utilized in the hairpretreatment compositions in conjunction with the quaternary ammoniumcompounds, which, as indicated above, represent particularly importantembodiments of the present invention, it is highly desirable, forinsuring clarity of the pretreatment compositions, to add particulartypes of acids to the compositions. Without the addition of an acid, thepH of the compositions will commonly be weakly basic. The addition oflow molecular weight monobasic organic acids, particularly formic acidor acetic acid, in amounts to reduce the pH of the composition to theorder of about 3.2 to about 3.7, optimally about 3.5, leaves solutionswhich are clear to the naked eye. While other acids can be used, such astartaric acid or citric acid or phosphoric acids, or other water-solublepolybasic acids, to produce solutions which have an acid pH of thegeneral order indicated above, their use is not preferred because theytend to produce solutions which are not clear and are of generallyturbid character. The pretreatment compositions will generally be formedso as to have a pH from about 3 to below 7, with a range of about 3.5 to6.0 being generally most desirable.

The following examples are illustrative of hair pretreatmentcompositions which are useful in the practice of the present invention.Other compositions can readily be prepared in light of the disclosuresand guiding principles and teachings provided herein. All numericalvalues represent percentages by weight of the compositions, andreference to "Balance" means the weight of the water to bring thecomposition to 100%.

EXAMPLE 1

    ______________________________________                                        Arquad C-50 (50% active).sup.1                                                                           4.0                                                N-Ethanolacetamide         15.0                                               Polyethylenimine (60,000 M.W.) (40% active)                                                              1.25                                               Volpo 20.sup.2             2.0                                                Formic acid (90% active)   1.4                                                Cellosize QP 100 MH.sup.3  0.37                                               Methyl Paraben.sup.4       0.1                                                Perfume                    Q.v.                                               Water (deionized)          Balance                                            ______________________________________                                         .sup.1 Coco trimethyl ammonium chloride                                       .sup.2 Nonionic emulsifier to solubilize perfume                              .sup.3 Nonionic thickener                                                     .sup.4 Preservative (methyl ester of p-hydroxy benzoic acid)             

There is nothing critical about the order of mixing of the ingredients.They may simply be admixed in the water, under conditions of stirring oragitation, heating slightly, if desired, to hasten the formation of thesolution, which, especially desirably, is clear to the naked eye.Generally, the perfume, where used, is added after the other ingredientshave been dissolved.

EXAMPLE 2

    ______________________________________                                        Arquad C-50 (50% active)   4.5                                                N-Ethanolacetamide         15.0                                               Polyethylenimine (60,000 M.W.) (40% active)                                                              1.5                                                Volpo 20                   2.0                                                Formic acid (90% active)   1.4                                                Cellosolve QP 100 MH       0.37                                               Methyl Paraben             0.1                                                Perfume                    Q.v.                                               Water (deionized)          Balance                                            ______________________________________                                    

EXAMPLE 3

    ______________________________________                                        Arquad C-50 (50% active)   4.0                                                N-Ethanolacetamide         15.0                                               Polyethylenimine (60,000 M.W.) (40% active)                                                              1.5                                                Volpo 20                   2.0                                                Orthophosphoric acid (75%) 0.5                                                Cellosize QP 100 MH        0.37                                               Methyl Paraben             0.1                                                Perfume                    Q.v.                                               Water (Deionized)          Balance                                            ______________________________________                                    

EXAMPLE 4

    ______________________________________                                        Arquad C-50 (50% active)   4.0                                                N-Ethanolacetamide         5.0                                                Polyethylenimine (60,000 M.W.) (40% active)                                                              1.25                                               Volpo 20                   2.0                                                Formic acid (90% active)   1.15                                               Cellosolve QP 100 MH       0.37                                               Methyl Paraben             0.1                                                Perfume                    Q.v.                                               Water (deionized)          Balance                                            ______________________________________                                    

EXAMPLE 5

    ______________________________________                                        Arquad C-50 (50% active)   4.0                                                N-Ethanolacetamide         15.0                                               Polyethylenimine (60,000 M.W.) (40% active)                                                              1.25                                               Volpo 20                   2.0                                                Formic acid (90% active)   1.15                                               Cellosolve QP 100 MH       0.37                                               Methyl Paraben             0.1                                                Perfume                    Q.v.                                               Water (deionized)          Balance                                            ______________________________________                                    

EXAMPLE 6

    ______________________________________                                        Arquad C-50 (50% active)   4.0                                                Polyethylenimine (60,000 M.W.) (40% active)                                                              1.5                                                Volpo 20                   0.2                                                Orthophosphoric acid (75%) 0.5                                                Cellosolve QP 100 MH       0.1                                                Methyl Paraben             0.1                                                Dow-Corning 472 Silicone Fluid                                                                           1.0                                                Perfume                    Q.v.                                               Water (deionized)          Balance                                            ______________________________________                                    

EXAMPLE 7

    ______________________________________                                        Arquad C-50 (50% active)   4.0                                                N-Ethanolacetamide         12.0                                               Cellosize PQ 100 MH        0.35                                               Methyl Paraben             0.1                                                Water (deionized)          Balance                                            ______________________________________                                    

EXAMPLE 8

    ______________________________________                                        Dodecyldimethylbenzyl ammonium chloride                                                                  2.0                                                N-Ethanolacetamide         10.0                                               Polyethylenimine (60,000 M.W.) (40% active)                                                              1.2                                                Acetic acid                1.0                                                Perfume                    Q.v.                                               Water (deionized)          Balance                                            ______________________________________                                    

EXAMPLE 9

    ______________________________________                                        Cetylpyridinium chloride   1.8                                                N-Ethanolacetamide         4.5                                                Polyethylenimine (40,000 M.W.) (40% active)                                                              1.7                                                Formic acid (90% active)   1.1                                                Water (deionized)          Balace                                             ______________________________________                                    

EXAMPLE 10

    ______________________________________                                        Lorol triethyl ammonium chloride                                                                         2.0                                                N-Ethanolacetamide         12.0                                               Polyethylenimine (60,000 M.W.) (40% active)                                                              1.3                                                Formic acid (90% active)   1.4                                                Cellosize QP 100 MH        0.3                                                Water (deionized)          Balance                                            ______________________________________                                    

The hair pretreatment compositions, as noted above, are most desirablymarketed and used in the form of aqueous solutions and are dispensedfrom conventional non-pressurized containers. If desired, they can alsobe packaged in atomizer containers or in conventional aerosol pressurepackages using volatile liquid propellants such as the well known"Freons."

In the treatment of the hair, in accordance with the present invention,as indicated above, the pretreatment quaternary ammonium composition isapplied to the hair and distributed therethrough reasonably thoroughlyand uniformly, in any suitable or convenient manner, as, for instance,by rubbing with the fingers. Then, promptly, or after waiting, ifdesired, for a convenient time but most desirably while the hair isstill wet, it is washed, in conventional manner, with a soap or with ashampoo containing a soap and/or a synthetic anionic detergent. Any ofnumerous known and commercially marketed soaps or shampoos, in liquid,cream or paste form, can be employed comprising or containing, forinstance, water-soluble soaps such as coconut oil fatty acid soaps orwater-soluble synthetic anionic detergents such as primary long chainalkyl sulfate salts exemplified by sodium lauryl sulfate ortriethanolamine lauryl sulfate or other salts of lauryl sulfate; orsalts of long chain alkylbenzene sulfonic acids such as sodium ortriethanolamine salts of linear or branched chain dodecylbenzenesulfonic acids; salts of sulfated monoglycerides such as sodium,ammonium and alkanolamine salts of coconut oil mixed fatty acidmonoglycerides; salts of sulfated tridecyl alcohol; or other knownanionic synthetic detergents conventionally used in anionicdetergent-containing shampoos. The soap or shampoo is then thoroughlyrinsed away with water in the usual manner. The hair is then ready to becombed and set or shaped as may be desired.

By employing quaternary ammonium compounds of the character describedabove in the pretreatment step, a substantial quantity of the quaternaryammonium compound penetrates into the scalp area and permeates the hairdeeply and quickly and is deposited as a film through its substantiveaction on the hair. Where a polyethylenimine is utilized in thepretreatment composition, it contributes its effect, also, in theformation of a film on the hair. At any rate, the film formation occursquickly throughout the body of the hair around the hair shafts, and alsoin the areas, particularly the deeper areas closely adjacent the scalpproper, and also where the hair may have been or has previously beendamaged due to other treatments and where, therefore, there may beinternal voids or crevices in the hair shafts. The films which areformed as a result of the pretreatment, or which form and are present asa result of the subsequent reaction with soap or anionic syntheticdetergent in the subsequent washing or shampooing step, appear to exerta favorable effect in the direction of repair or alleviation of damagedhair shafts.

After the washing or shampooing of the pretreated hair and thesubsequent rinsing with water, it appears that appreciable filmed hairshafts remain, particularly in the cracks and crevices, indeed to agreater extent than is the situation with prior known practices in theart, and which are of a character such that, overall, the improvementswhich result from the practice of the present invention are achieved orbrought about.

By way of further explanation, it may be pointed out that it isdesirable to maintain long chain-or fatty chain-containing substanceswithin cracks and crevices of individual hair strands. These cracks andcrevices generally develop during the process of combing, curling,brushing and application of other cosmetic treatments to the hair. Theyare the physical result which is involved in hair damage. The presenceof these fatty deposits within the hair strand make it more supple, lessbrittle, and thus, helps to prevent further breakage on combing.

It is important, to the practice of the present invention for mosteffective results, to get deep penetration during the short timeavailable in treating hair under practical conditions. By making use ofsmall, water-soluble, rapidly diffusing quaternary ammonium molecules atthe first stage, as distinguished from polymeric cationic substances orhigh molecular weight relatively poorly water-soluble substances suchas, for instance, distearyldimethyl ammonium chloride, generally maximalpenetration of the hair shaft is effected. Then, in the subsequentshampooing step, where anionic shampoos are used, and particularly wherethey are water-soluble and have molecular weights of the general orderof those of the water-soluble quaternary ammonium compounds used in thepretreatment step, or somewhat higher or somewhat lower molecularweights than that of said quaternary ammonium compounds, deeppenetration of said anionic material into the hair shaft also appears totake place. When the quaternary ammonium compound and the anionicdetergent come into contact, a reaction takes place resulting in theformation of a double long chain-or fatty-chain like salt which isessentially insoluble in the rinse water and remains in place within,and, generally relatively deeply within, the hair shaft.

Polymeric cationic materials and other cationic materials of unduly highmolecular weight diffuse, at best, very slowly into hair strands. Hence,deposition of such cationic materials is not specific to the deep cracksand crevices in the hair strands but, on the contrary, tends to becomerelatively uniformly distributed over the hair, an effect which isundesirable. Thus, for instance, coating the surface of the hair with acationic polymer tends to weight down individual hair strands. Thisadded weight tends to make the hair flatter from the scalp and resemblesin appearance the effect of dirt on the hair.

In the practice of the present invention, the reaction product whichresults between the water-soluble quaternary ammonium compound and theanionic detergent of the shampoo, under the particular conditions underand in the environment in which it is formed, is beneficial to theobjectives of the invention. Thus, when in contact with the largeamounts of anionic materials in the shampooing step, the reactionproduct formed from said anionic material and the water-solublequaternary ammonium compound from the pretreatment step, is solubilizedinto the aqueous phase. Deeply imbedded material does not tend to comein contact with excess anionic during the shampooing process. However,material deposited in more available locations such as the hair shaftsurface is solubilized and removed during the shampoo process. As aconsequence, only the deeply imbedded material remains in the hair afterthe shampoo process. In essence, the "repair" material is depositedefficiently where it is needed without the negative effect of having toomuch material left on the hair as is the case when a cationic polymer isused. In other words, both the water-soluble quaternary ammoniumcompound and the water-soluble anionic detergent are able to penetratedeeply into the hair shaft. There they form an insoluble compound whichstays in place through many later shampoos, adding body and supplenessto the hair strand.

For convenience of expression, the term "anionic" shampoo is used in theclaims to mean soaps, as well as shampoos for washing the hair in whichthe shampoos contain as an essential cleanser or detergent one or moresoaps and/or anionic synthetic detergents, with or without variousadditional or supplemental ingredients illustrative of which arenonionic surfactants, alkanolamides, thickeners, etc.

What is claimed is:
 1. A method of treating hair to improve themanageability thereof, which comprises initially contacting the hairwith a dilute aqueous composition containing a water-soluble quaternaryammonium compound containing at least one long chain alkyl radicalattached to the central nitrogen atom thereof, and then shampooing thehair with an anionic shampoo.
 2. The method of claim 1, in which thequaternary ammonium compound has the formula ##STR2## wherein R¹ is C₈-C₁₈ alkyl; each of R², R³ and R⁴ is C₁ -C₃ alkyl, the total number ofcarbon atoms in R², R³ and R⁴ not exceeding 6; and A is an innocuousanion.
 3. The method of claim 1, in which the dilute aqueous compositioncontaining the quaternary ammonium compound also contains at least onemember of the group of N-ethanolacetamide and a fatty acid ethanolamidein which the fatty acid comprises predominately lauric acid.
 4. Themethod of claim 1, in which the dilute aqueous composition containingthe quaternary ammonium compound also contains polyethylenimine having amolecular weight between about 10,000 and about 70,000.
 5. The method ofclaim 3, in which the dilute aqueous composition also containspolyethylenimine having a molecular weight between about 10,000 andabout 70,000.
 6. A method of treating hair to improve the manageabilitythereof, which comprises initially contacting the hair with a diluteaqueous solution, clear to the naked eye, containing a water-solublequaternary ammonium compound containing at least one long chain alkylradical attached to the central nitrogen atom thereof,N-ethanolacetamide, polyethylenimine having a molecular weight betweenabout 10,000 and about 70,000, and at least one acid selected from thegroup consisting of formic acid and acetic acid having a pH in the rangeof about 3 to below 7, and subsequently shampooing the hair with ananionic shampoo.
 7. The method of claim 6, in which the dilute aqueoussolution contains the stated ingredients in approximately the followingproportions by weight of said solution:

    ______________________________________                                        Water                   70 to 90%                                             Quatenary ammonium compound                                                                          0.5 to 4%                                              N-Ethanolacetamide      3 to 18%                                              Polyethylenimine       0.5 to 5%.                                             ______________________________________                                    


8. A composition for pretreatment of hair prior to shampooing saidpretreated hair with an anionic shampoo, said composition comprising amajor proportion of water, and minor proportions of a readilywater-soluble quaternary ammonium compound containing at least one longchain alkyl radical attached to the central nitrogen atom thereof andpolyethylenimine having a molecular weight in the range of about 10,000to about 70,000.
 9. The composition according to claim 8, which alsoincludes a minor proportion of at least one member of the group ofN-ethanolacetamide and a fatty acid ethanolamide in which the fatty acidcomprises predominately lauric acid.
 10. The composition of claim 8,which also includes at least one water-soluble acid and has a pH in therange of about 3 to below
 7. 11. A composition according to claim 8, inwhich the quaternary ammonium compound has the formula ##STR3## whereinR¹ is C₈ -C₁₈ alkyl; each of R², R³ and R⁴ is C₁ -C₃ alkyl, the totalnumber of carbon atoms in R², R³ and R⁴ not exceeding 6; and A is aninnocuous anion.
 12. The composition according to claim 11, wherein R¹is predominately dodecyl; each of R², R³ and R⁴ is methyl; and A ischlorine or bromine.
 13. The composition of claim 10, in which the acidis formic acid or acetic acid.
 14. A composition for pretreatment ofhair prior to shampooing said pretreated hair with an anionic shampoo,said composition containing from about 70 to about 90% of water, fromabout 0.5 to about 4% of a readily water-soluble quaternary ammoniumcompound containing at least one long chain alkyl radical attached tothe central nitrogen atom thereof, from about 3 to 18% ofN-ethanolacetamide, and from about 0.2 to 5% of polyethylenimine havinga molecular weight in the range of about 10,000 to about 70,000, saidpercentages being by weight of the composition.
 15. A composition forpretreatment of hair prior to shampooing said pretreated hair with ananionic shampoo, said composition comprising a clear aqueous solutioncontaining from about 70 to about 90% of water, from about 0.5 to about4% of a readily water-soluble quaternary ammonium compound having theformula ##STR4## where R¹ is alkyl containing predominately from 10 to14 carbon atoms; R², R³ and R⁴ are each methyl; and A is chlorine orbromine; from about 3 to 18% of N-ethanolacetamide, and from about 0.2to 2% of polyethylenimine having a molecular weight between about 10,000and about 70,000, said percentages being by weight of the composition.16. A composition for pretreatment of hair prior to shampooing saidpretreated hair with an anionic shampoo, said composition comprising aclear aqueous solution containing from about 70 to about 85% of water,from about 1.5 to about 2% of a readily water-soluble quaternaryammonium compound having the formula ##STR5## where R¹ is alkylcontaining predominately from 10 to 14 carbon atoms; R², R³ and R⁴ areeach methyl; and A is chlorine or bromine; from about 12 to 15% ofN-ethanolacetamide, and from bout 1 to 2% of polyethylenimine having amolecular weight between about 40,000 to about 60,000, said percentagesbeing by weight of the composition.
 17. The composition according toclaim 16, which also includes at least one water-soluble acid and has apH in the range of about 3 to below
 7. 18. The composition of claim 17,in which the acid is formic acid or acetic acid.